-LRB- CNN -RRB- -- Lawmakers in Uganda are preparing to vote on a new anti-homosexuality bill that proposes tough jail sentences for consensual same-sex behavior .

Homosexual acts are already illegal in the east African nation , where most gays and lesbians face physical attacks and are treated as social outcasts , but the new bill proposes harsher penalties .

Uganda 's maximum penalty would be life in prison .

Amnesty International said it was `` extremely concerned '' about the bill and called on the Ugandan parliament not to pass it .

`` The bill would have lasting , harmful effects on Ugandans who are thought to breach its far-reaching provisions and it would significantly hamper the work of human rights defenders and public health professionals , '' the rights group said .

`` Although Amnesty International has been informed that some provisions of the bill have been amended , the content of these amendments have not been made publicly available .

`` This bill violates the principle of nondiscrimination as guaranteed under international and regional treaties to which Uganda is a party . ''

`` We are outraged , '' said Noel Kututwa , the rights group 's director for southern Africa . `` This goes beyond the principle of nondiscrimination . It goes against the principle of privacy of individuals . And sexual orientation is really a question of the right of an individual to choose how they want to live their lives . ''

Uganda 's parliamentary speaker has reportedly said she wants the legislation to pass before Christmas .

World leaders condemned the anti-gay legislation when it was first proposed in 2009 . Some nations have also threatened to withhold aid to Uganda over its record on same-sex rights .

Prominent gay rights activist David Kato was beaten to death in the country in 2011 , a slaying that rights activists believe was motivated by homophobia .

A British producer was also briefly jailed in Uganda in September this year for staging without permission a play about the challenges facing homosexuals in the African nation .

If convicted , David Cecil could be imprisoned for two years , his lawyer said .

Homosexuality is illegal in most countries in Africa , where sodomy laws were introduced during colonialism .

The death penalty can be imposed in a handful of nations worldwide for consensual same-sex relations , including Nigeria , Sudan , Mauritania , Saudi Arabia and Iran , according to the International Lesbian , Gay , Bisexual , Trans and Intersex Association .

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CNN 's Victoria Eastwood contributed to this report .

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Homosexual acts are already illegal in Uganda , but the bill proposes harsher penalties

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Amnesty International says the legislation would have `` lasting , harmful effects ''

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Uganda 's parliamentary speaker has reportedly said she wants the bill to pass before Christmas